--- /dev/null
+// elfcpp_swap.h -- Handle swapping for elfcpp -*- C++ -*-
+
+// Copyright 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
+// Written by Ian Lance Taylor <iant@google.com>.
+
+// This file is part of elfcpp.
+
+// This program is free software; you can redistribute it and/or
+// modify it under the terms of the GNU Library General Public License
+// as published by the Free Software Foundation; either version 2, or
+// (at your option) any later version.
+
+// In addition to the permissions in the GNU Library General Public
+// License, the Free Software Foundation gives you unlimited
+// permission to link the compiled version of this file into
+// combinations with other programs, and to distribute those
+// combinations without any restriction coming from the use of this
+// file. (The Library Public License restrictions do apply in other
+// respects; for example, they cover modification of the file, and
+/// distribution when not linked into a combined executable.)
+
+// This program is distributed in the hope that it will be useful, but
+// WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+// Library General Public License for more details.
+
+// You should have received a copy of the GNU Library General Public
+// License along with this program; if not, write to the Free Software
+// Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA
+// 02110-1301, USA.
+
+// This header file defines basic template classes to efficiently swap
+// numbers between host form and target form. When the host and
+// target have the same endianness, these turn into no-ops.
+
+#ifndef ELFCPP_SWAP_H
+#define ELFCPP_SWAP_H
+
+#include <stdint.h>
+
+// We need an autoconf-generated config.h file for endianness and
+// swapping. We check two macros: WORDS_BIGENDIAN and
+// HAVE_BYTESWAP_H.
+
+#include "config.h"
+
+#ifdef HAVE_BYTESWAP_H
+#include <byteswap.h>
+#else
+// Provide our own versions of the byteswap functions.
+inline uint16_t
+bswap_16(uint16_t v)
+{
+ return ((v >> 8) & 0xff) | ((v & 0xff) << 8);
+}
+
+inline uint32_t
+bswap_32(uint32_t v)
+{
+ return ( ((v & 0xff000000) >> 24)
+ | ((v & 0x00ff0000) >> 8)
+ | ((v & 0x0000ff00) << 8)
+ | ((v & 0x000000ff) << 24));
+}
+
+inline uint64_t
+bswap_64(uint64_t v)
+{
+ return ( ((v & 0xff00000000000000ULL) >> 56)
+ | ((v & 0x00ff000000000000ULL) >> 40)
+ | ((v & 0x0000ff0000000000ULL) >> 24)
+ | ((v & 0x000000ff00000000ULL) >> 8)
+ | ((v & 0x00000000ff000000ULL) << 8)
+ | ((v & 0x0000000000ff0000ULL) << 24)
+ | ((v & 0x000000000000ff00ULL) << 40)
+ | ((v & 0x00000000000000ffULL) << 56));
+}
+#endif // !defined(HAVE_BYTESWAP_H)
+
+// gcc 4.3 and later provides __builtin_bswap32 and __builtin_bswap64.
+
+#if defined(__GNUC__) && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3))
+#undef bswap_32
+#define bswap_32 __builtin_bswap32
+#undef bswap_64
+#define bswap_64 __builtin_bswap64
+#endif
+
+namespace elfcpp
+{
+
+// Endian simply indicates whether the host is big endian or not.
+
+struct Endian
+{
+ public:
+ // Used for template specializations.
+ static const bool host_big_endian =
+#ifdef WORDS_BIGENDIAN
+ true
+#else
+ false
+#endif
+ ;
+};
+
+// Valtype_base is a template based on size (8, 16, 32, 64) which
+// defines the type Valtype as the unsigned integer, and
+// Signed_valtype as the signed integer, of the specified size.
+
+template<int size>
+struct Valtype_base;
+
+template<>
+struct Valtype_base<8>
+{
+ typedef uint8_t Valtype;
+ typedef int8_t Signed_valtype;
+};
+
+template<>
+struct Valtype_base<16>
+{
+ typedef uint16_t Valtype;
+ typedef int16_t Signed_valtype;
+};
+
+template<>
+struct Valtype_base<32>
+{
+ typedef uint32_t Valtype;
+ typedef int32_t Signed_valtype;
+};
+
+template<>
+struct Valtype_base<64>
+{
+ typedef uint64_t Valtype;
+ typedef int64_t Signed_valtype;
+};
+
+// Convert_endian is a template based on size and on whether the host
+// and target have the same endianness. It defines the type Valtype
+// as Valtype_base does, and also defines a function convert_host
+// which takes an argument of type Valtype and returns the same value,
+// but swapped if the host and target have different endianness.
+
+template<int size, bool same_endian>
+struct Convert_endian;
+
+template<int size>
+struct Convert_endian<size, true>
+{
+ typedef typename Valtype_base<size>::Valtype Valtype;
+
+ static inline Valtype
+ convert_host(Valtype v)
+ { return v; }
+};
+
+template<>
+struct Convert_endian<8, false>
+{
+ typedef Valtype_base<8>::Valtype Valtype;
+
+ static inline Valtype
+ convert_host(Valtype v)
+ { return v; }
+};
+
+template<>
+struct Convert_endian<16, false>
+{
+ typedef Valtype_base<16>::Valtype Valtype;
+
+ static inline Valtype
+ convert_host(Valtype v)
+ { return bswap_16(v); }
+};
+
+template<>
+struct Convert_endian<32, false>
+{
+ typedef Valtype_base<32>::Valtype Valtype;
+
+ static inline Valtype
+ convert_host(Valtype v)
+ { return bswap_32(v); }
+};
+
+template<>
+struct Convert_endian<64, false>
+{
+ typedef Valtype_base<64>::Valtype Valtype;
+
+ static inline Valtype
+ convert_host(Valtype v)
+ { return bswap_64(v); }
+};
+
+// Convert is a template based on size and on whether the target is
+// big endian. It defines Valtype and convert_host like
+// Convert_endian. That is, it is just like Convert_endian except in
+// the meaning of the second template parameter.
+
+template<int size, bool big_endian>
+struct Convert
+{
+ typedef typename Valtype_base<size>::Valtype Valtype;
+
+ static inline Valtype
+ convert_host(Valtype v)
+ {
+ return Convert_endian<size, big_endian == Endian::host_big_endian>
+ ::convert_host(v);
+ }
+};
+
+// Swap is a template based on size and on whether the target is big
+// endian. It defines the type Valtype and the functions readval and
+// writeval. The functions read and write values of the appropriate
+// size out of buffers, swapping them if necessary. readval and
+// writeval are overloaded to take pointers to the appropriate type or
+// pointers to unsigned char.
+
+template<int size, bool big_endian>
+struct Swap
+{
+ typedef typename Valtype_base<size>::Valtype Valtype;
+
+ static inline Valtype
+ readval(const Valtype* wv)
+ { return Convert<size, big_endian>::convert_host(*wv); }
+
+ static inline void
+ writeval(Valtype* wv, Valtype v)
+ { *wv = Convert<size, big_endian>::convert_host(v); }
+
+ static inline Valtype
+ readval(const unsigned char* wv)
+ { return readval(reinterpret_cast<const Valtype*>(wv)); }
+
+ static inline void
+ writeval(unsigned char* wv, Valtype v)
+ { writeval(reinterpret_cast<Valtype*>(wv), v); }
+};
+
+// We need to specialize the 8-bit version of Swap to avoid
+// conflicting overloads, since both versions of readval and writeval
+// will have the same type parameters.
+
+template<bool big_endian>
+struct Swap<8, big_endian>
+{
+ typedef typename Valtype_base<8>::Valtype Valtype;
+
+ static inline Valtype
+ readval(const Valtype* wv)
+ { return *wv; }
+
+ static inline void
+ writeval(Valtype* wv, Valtype v)
+ { *wv = v; }
+};
+
+// Swap_unaligned is a template based on size and on whether the
+// target is big endian. It defines the type Valtype and the
+// functions readval and writeval. The functions read and write
+// values of the appropriate size out of buffers which may be
+// misaligned.
+
+template<int size, bool big_endian>
+struct Swap_unaligned;
+
+template<bool big_endian>
+struct Swap_unaligned<8, big_endian>
+{
+ typedef typename Valtype_base<8>::Valtype Valtype;
+
+ static inline Valtype
+ readval(const unsigned char* wv)
+ { return *wv; }
+
+ static inline void
+ writeval(unsigned char* wv, Valtype v)
+ { *wv = v; }
+};
+
+template<>
+struct Swap_unaligned<16, false>
+{
+ typedef Valtype_base<16>::Valtype Valtype;
+
+ static inline Valtype
+ readval(const unsigned char* wv)
+ {
+ return (wv[1] << 8) | wv[0];
+ }
+
+ static inline void
+ writeval(unsigned char* wv, Valtype v)
+ {
+ wv[1] = v >> 8;
+ wv[0] = v;
+ }
+};
+
+template<>
+struct Swap_unaligned<16, true>
+{
+ typedef Valtype_base<16>::Valtype Valtype;
+
+ static inline Valtype
+ readval(const unsigned char* wv)
+ {
+ return (wv[0] << 8) | wv[1];
+ }
+
+ static inline void
+ writeval(unsigned char* wv, Valtype v)
+ {
+ wv[0] = v >> 8;
+ wv[1] = v;
+ }
+};
+
+template<>
+struct Swap_unaligned<32, false>
+{
+ typedef Valtype_base<32>::Valtype Valtype;
+
+ static inline Valtype
+ readval(const unsigned char* wv)
+ {
+ return (wv[3] << 24) | (wv[2] << 16) | (wv[1] << 8) | wv[0];
+ }
+
+ static inline void
+ writeval(unsigned char* wv, Valtype v)
+ {
+ wv[3] = v >> 24;
+ wv[2] = v >> 16;
+ wv[1] = v >> 8;
+ wv[0] = v;
+ }
+};
+
+template<>
+struct Swap_unaligned<32, true>
+{
+ typedef Valtype_base<32>::Valtype Valtype;
+
+ static inline Valtype
+ readval(const unsigned char* wv)
+ {
+ return (wv[0] << 24) | (wv[1] << 16) | (wv[2] << 8) | wv[3];
+ }
+
+ static inline void
+ writeval(unsigned char* wv, Valtype v)
+ {
+ wv[0] = v >> 24;
+ wv[1] = v >> 16;
+ wv[2] = v >> 8;
+ wv[3] = v;
+ }
+};
+
+template<>
+struct Swap_unaligned<64, false>
+{
+ typedef Valtype_base<64>::Valtype Valtype;
+
+ static inline Valtype
+ readval(const unsigned char* wv)
+ {
+ return ((static_cast<Valtype>(wv[7]) << 56)
+ | (static_cast<Valtype>(wv[6]) << 48)
+ | (static_cast<Valtype>(wv[5]) << 40)
+ | (static_cast<Valtype>(wv[4]) << 32)
+ | (static_cast<Valtype>(wv[3]) << 24)
+ | (static_cast<Valtype>(wv[2]) << 16)
+ | (static_cast<Valtype>(wv[1]) << 8)
+ | static_cast<Valtype>(wv[0]));
+ }
+
+ static inline void
+ writeval(unsigned char* wv, Valtype v)
+ {
+ wv[7] = v >> 56;
+ wv[6] = v >> 48;
+ wv[5] = v >> 40;
+ wv[4] = v >> 32;
+ wv[3] = v >> 24;
+ wv[2] = v >> 16;
+ wv[1] = v >> 8;
+ wv[0] = v;
+ }
+};
+
+template<>
+struct Swap_unaligned<64, true>
+{
+ typedef Valtype_base<64>::Valtype Valtype;
+
+ static inline Valtype
+ readval(const unsigned char* wv)
+ {
+ return ((static_cast<Valtype>(wv[0]) << 56)
+ | (static_cast<Valtype>(wv[1]) << 48)
+ | (static_cast<Valtype>(wv[2]) << 40)
+ | (static_cast<Valtype>(wv[3]) << 32)
+ | (static_cast<Valtype>(wv[4]) << 24)
+ | (static_cast<Valtype>(wv[5]) << 16)
+ | (static_cast<Valtype>(wv[6]) << 8)
+ | static_cast<Valtype>(wv[7]));
+ }
+
+ static inline void
+ writeval(unsigned char* wv, Valtype v)
+ {
+ wv[0] = v >> 56;
+ wv[1] = v >> 48;
+ wv[2] = v >> 40;
+ wv[3] = v >> 32;
+ wv[4] = v >> 24;
+ wv[5] = v >> 16;
+ wv[6] = v >> 8;
+ wv[7] = v;
+ }
+};
+
+} // End namespace elfcpp.
+
+#endif // !defined(ELFCPP_SWAP_H)
projects / msp430-binutils.git / blobdiff